code: def minmax_auto_scale(img, as_uint16):
      """
      Utility function for rescaling all pixel values of input image to fit the range of uint8.
      Rescaling method is min-max, which is all pixel values are normalized to [0, 1] by using img.min() and img.max()
      and then are scaled up by 255 times.
      If the argument `as_uint16` is True, output image dtype is np.uint16 and the range of pixel values is [0, 65535] (scaled up by 65535 after normalized to [0, 1]).
  
      :param img (numpy.ndarray): input image.
      :param as_uint16: If True, output image dtype is uint16.
      :return: numpy.ndarray
      """
  
      if as_uint16:
          output_high = 65535
          output_type = np.uint16
      else:
          output_high = 255
          output_type = np.uint8
  
      return rescale_pixel_intensity(
          img,
          input_low=img.min(),
          input_high=img.max(),
          output_low=0,
          output_high=output_high,
          output_type=output_type,
      )
  
file_path: nnabla/python/src/nnabla/utils/image_utils/__init__.py
imports: from __future__ import absolute_import
  import numpy
  from .backend_manager import backend_manager
  from .backend_events.common import rescale_pixel_intensity
label_desc: Use image node_id 4 for calling a global function with example usage: minmax_auto_scale(img, as_uint16) and returns: rescale_pixel_intensity